Psychology: Brain researcher explains why we often start pondering when we fall asleep

Another night like that. Actually, I should have been asleep a long time ago. About an hour ago, while still sitting on the sofa in my living room, I was already so tired that it took me an agonizing ten minutes to get up, brush my teeth, and finally fall into bed. But shortly after my head has found its place on my pillow, the thoughts come:

Should I have ordered the shoes one size bigger? They are probably too small for me and no longer available in the right size if I want to reorder them in a few days. Maybe that’s a sign that I shouldn’t buy the shoes at all. I’ll give it a shot and see what happens. Or should I order them now? Would be ideal for my vacation. Oh man, I still have to apply for that. But first I have to decide whether I’d rather take it in August or September. My sister’s birthday is in September, what am I actually getting her? …

And somewhere inside me, the accompanying music is Post Malone with “Circles” playing on a continuous loop.

Where’s that off button when you need it? Why do I, like many other people, sometimes just not stop thinking when I want to sleep – and I’m terribly tired at that? I spoke to the neurobiologist Professor Doctor Martin Korte about this.

Thoughts and ideas can trigger a stress response

“In such a moment, several aspects usually come together,” says the brain researcher. “It is fundamentally important that what our brain simulates can cause a physical reaction. For example, the idea of ​​a threatening situation can trigger stress in us, even if we know that the threat is not real.”

Just the thought of being barefoot on vacation triggers a stress response and an increase in adrenaline and/or cortisol levels in my blood. Both hormones are stimulants that get my circulation going: my blood pressure rises, my heartbeat accelerates. This in turn registers my brain – and immediately turns up the volume control of my inner turntable a bit. party is on Instead of dozing off, I worry about vacation planning, birthday presents, applying for a new passport, a bookshelf that I should have gotten a long time ago because the books are piled up on my living room floor, and then shoes again. Run away, but we’re running in circles. i like this song But not when I want to sleep.

Unsolved problems are sleeping enemy number one

“Often this cascade of thoughts that keeps people from falling asleep is triggered by the fact that they quickly looked up something on their cell phone or did something just before going to bed,” says Martin Korte. For example, the reaction to a message that we have written, or, even more dangerous, no reaction can provoke questions in us à la “did I do something wrong?”, “what do you mean now?” and so forth. Questions, on the other hand, that is open, unsolved problems, are fatal shortly before falling asleep, because: “If there is something to which our brain reacts sensitively, it is ambiguity and open questions,” says Martin Korte. Unresolved conflicts are a nightmare for our brain. And very stressful. In principle, tiredness hardly stands a chance against an unsolved problem once it has followed us to bed.

However, the risk of encountering unresolved conflicts is not the only argument against hanging around on your cell phone just before going to bed: The light that smartphones, tablets and other modern screens emit, especially the blue light, disturbs our sleep -wake cycle. “The cones in our eyes, i.e. the photoreceptors, send a signal to the brain region that controls our 24-hour daily rhythm that it’s not time to sleep when they see blue light,” explains the brain researcher. We interpret blue light as a signal for the day, which is why the neurobiologist advises using smartphones and the like in the evening, if at all, then only in night mode, in which the blue light is suppressed.

Neurologically meaningful evening routines

All in all, according to Martin Korte, “good sleep hygiene” can help to ensure that cascades of thoughts at bedtime remain an exception in our everyday life: if possible, go to bed at about the same time every evening, take a break from all screens for at least half an hour beforehand and don’t turn on the bright lights, don’t overeat too late, don’t go to bed right after your power workout (this should be done two to three hours before your target bedtime). The room temperature in our bedroom is ideally between 17 and 20 degrees and a hot bath or shower in the evening can also help (check out this article for more sleep tips). However, should a tricky question about shoes come up and keep us awake, the brain researcher recommends getting out of bed and reading for a few more minutes – or thinking the problem through to the end, or getting rid of the question by we just order the shoes to be on the safe side (in night mode, of course), because we can always send them back.

The fact that such simple, physical measures actually help is because our body and our thought cascades are very, very closely related. Our brain is part of our body and our thoughts are a product of it. Therefore, thoughts can block our sleep, and external factors happening to our feet, our skin, our stomach, and the cones in our eyes can affect our thinking. The fact that there is no button to turn off our thoughts and our inner record player forces us to recognize, accept and respect this connection. In addition, this fact can motivate us to organize our lives in such a way that at the end of the day there are not too many unsolved problems that keep us from sleeping. Against this background, it’s probably a good thing that there’s no such thing as an off button, maybe even ingenious. Anyway, I’m grateful for that, when I think about it. Struggling with that would just mean another unnecessary conflict that would keep me up at night.

Professor Doctor Martin Korte is a neurobiologist and head of the department “Cellular Neurobiology” at the Technical University of Braunschweig. His research focuses include the cellular basis of learning and memory and the interaction between the immune system and the brain in the development of Alzheimer’s disease. In his books “Hirngeflüster”, “We are memory” and “Jung im Kopf” he prepares findings from brain research that are relevant to everyday life and for a wide audience. TV viewers may know Martin Korte from the RTL quiz show with Günther Jauch “Bin ich smarter than…”, for which he developed the questions.

For our “thought out” column, the neurobiologist will from now on regularly address phenomena that puzzle us in our everyday life and make us wonder about ourselves. Would you like an explanation of such a phenomenon? Then you are very welcome to send our author your suggested topic by email ([email protected]).

Bridget